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Implement Serial Port Output with UART 16550

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Write a PS/2 Keyboard Interrupt Service Routine Program the DMA Controller for Memory Transfers

Language

Compiler

2.0s Limit 256MB

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Implementation

Implement serial port driver in C.

Requirements:

Define UART register addresses for COM1
Implement serial_init() setting baud rate and line control
Implement serial_send_byte() polling LSR
Implement serial_print() sending strings
Implement serial_received() checking LSR
Implement serial_read() reading one byte
Show divisor calculation for 9600 baud
Show 8N1 configuration
Demonstrate sending "Hello, UART!"
Show FIFO enable

Test:

Show serial initialized
Show baud rate set
Show character transmitted
Show string sent
Show receive check

Why This Matters

This exact COM1-at-0x3F8 UART 16550 setup is what the Linux kernel's `earlyprintk=serial` and `console=ttyS0` boot options use to capture kernel messages before any graphics driver loads, and QEMU's `-serial stdio` flag redirects precisely this port to your terminal. It remains the single most reliable debugging channel in OS development because it works even when video output is completely broken.

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Validation Suite

main.c

Workspace 1.0

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